Textile material and the manufacture thereof



Patented Oct. 27,

TEXTILE MATERIAL AND THE MANU- FACTURE THEREOF v william AlexanderDickie,'Donald Finlayson, and Percy Frederick Combe Sowtcr, Spondon,near Derby, England, assignors to Celanese Corporation of America, acorporation of Delaware No Drawing.. Application June 24, 1932, SerialNo. 619,122. In Great Britain Augult 92, 1931 4 Claims. (01. 28-1) Thisinvention relates to textile yarns and fabrics, and in particular toyarns capable of producing crepe effects and fabrics exhibiting suchcrepe effects. The invention is especially con- 5 cerned with theme ofyarns containing cellulose derivatives in the production of fabricsexhibiting crepe or like figured effects. I

It is well known that, textile materials exhibiting crepe efiects areordinarily produced by employing in their construction highly twistedyarns either in the weft or warp or both, which yarns produce ashrinking of the fabric on scouring, with the result that crpe effectsappear. Crepe effects are, however, only obtained with difficulty by theemployment of highly twisted crpe threads of cellulose derivatives. Ithas, however, been found possible to produce satisfactory crpe efiectswhen using these materials by application tothe crepe threads and/or tothe fabrics containing the crepe threads of a substance adapted to swellthe material of the threads and/or to apply a size tothe threads, whichsize is adapted to be swollen in the scouring treatment so. as to assistin the production of the crpeefiect. Such treatments are described in U.S. Patents Nos. 1,993,992 and 1,995,296 and British Patents Nos.343,444; 348,589; 351,999; 352,451, and 357,084.

A further method which has been adopted for 30 treating these materialsis described in British Pat. No. 378,910, according to which chemicalmeans are utilized to effect the shrinkage of the highly twisted crepethreads in fabrics contain ingthem. Further, it has been found thatwithI yarns consisting of filaments of line or very fine filament denier,for example 3, 1 -1-or less, especially if such yarns are twisted to ahigher degree than usual, for-example to 80-85 turns per inch or more,improved crepe effects may'be obtained. Again, it is also advantageousteapply the crepe twist in t'wo or more stages, between each or any ofwhich size may be imparted to the yarns. Further, in such treatmentsemploying two or more stages of twisting, the yarn maybe treated withsteam or other vapours-between stages as described in British Patent No.386,344. Yet other methods of producing crepe threads from cellulosederivatives are described in British Pat. No. 386,344, fcr'example byapply.-

two stages with intermediate w/etting 0f the 5 yarns which have beenuniformly or intermiting the requisite high degree of twist in at least,lulose-derivative.)

tently stretched beyond the elastic limit or contain filaments whichhave been stretchedto different extents as described in U. S. Pat. No.1,976,201 and Br. Pat. No. 371,910.

It has now been found that a still further im- 5 provement in the crepeeffect obtainable when using yarns of cellulose derivatives can beachieved by the employment of yarns which have been shrunk withmethylene chloride, chloroform, tetrachlorethane, dichlorethylene, ethyl10 acetate or like latent solvents for the cellulose derivative. Suchyarns have an increased extensibility, which is of advantage when hightwists are to be inserted, and in the employment of such yarns, not onlyis a good figure obtained 15 on the fabrics, but they also have anelastic appearance, soft handle, and are very closely resembling thatobtained in crpe fabrics made from natural silk. These valuable resultsare obtained without the tensile strength or other valuable propertiesof the cellulose derivative yarns being in anyway deleteriouslyaffected. Moreover, in the application of the shrinldng agents to theyarns the wide choice of conditions possiblein the treatment avoidsthere being any undesired variation in the lustre of the yarns. The saidagents, though not actually solvents for the commercial acetone-solublecellulose acetate are bapable of swelling the cellulose acetate to avery high degree. When mixed with compara- 30 tively'small proportionsof other agents, and particularly alcohols, which are not themselvessolvents for the. cellulose acetate, a solvent mixture oduced. ,(Themethylene chloride and like 2, ts are termed latent solven for the cel-3 The methylene chloride or like shrinking agent may be applied by anysuitable means to the yarns priorto the application of the requisitehigh dethough the precise effect may vary somewhat with p the particulartype of yarn treated, and with'its method of preparation, and theconcentration of the agent used, with the esteror ether contentontheicellulose ester or ether, and of course, with the particularcellulose ester or ether.

Thus for instance with the ordinary commercial acetone-soluble celluloseacetate the amount of shrinking achieved with methylene chloride maydepend upon the method of preparation of the yarn. It has been foundthat the shrinking is in general greater with the modern high tenacitywet-spun yarns than it is with the commercial dry-spun yarns, and,moreover, with the dryspun yarns it is greater if the yarn has beenpreviously subjected to a stretching treatment. As is the case with theyarns described in British Patent No. 380,504, methylene chloride orlike agent used alone produces in general a very high degree ofshrinkage, and it is preferable to modify the effect somewhat by theaddition of suitable diluents to the methylene chloride or like agent,as for example, benzene, toluene, xylene or other cyclic hydrocarbons,benzine, petrol ether, kerosene or other hydrocarbons of the aliphaticor petroleum series, carbon tetrachloride, trichlorethylene,perchlorethylene and other chlorinated or halogenated compounds whichare inert or comparatively inert towards the cellulose derivative. It ispreferable to restrain the high shrinking action of the methylenechloride or like agent by the addition of such a diluent so as to reducethe concentration of the methylene chloride to about 60 or 70%. Benzeneand carbon tetrachloride are very suitable diluents for use withmethylene-chloride in such a concentration. If desired, the amount ofshrinkage may be modified by exerting a suitable tension upon the yarnunder treatment, such tension being either insufficient to prevent someshrinkage or being suflicient to prevent shrinkage, the tension beingsubsequently decreased so as to enable the shrinkage to take place.

After the application of the shrinking agent, the yarn may, if desired,be rinsed in a liquid inert to the yarn, but forming a solvent for anyconstituent of the shrinking liquid which would normally tend toplastify the yarn if allowed to concentrate thereon during drying. Thusfor example, if chloroform is applied to the yarn in admixture withbenzene, the concentration of chloroform on the .yarn due to therelatively rapid evaporation of benzene may be obviated by rinsing theyarn in benzene before drying. It may be desirable to lubricate the yarnbefore or during the twisting operation. For this purpose, alubricantmay be added to the rinsing liquid, if used, c. g. 3% of oliveoil in benzene may be employed for rinsing. Alternatively or inaddition, a lubricant may be applied to the yarn, before or duringtwisting, by running the yarn over wicks, rods,

rollers or the like, moistened with the lubricant to be applied.

Yarns shrunk in the manner above described maybe given a requisite highdegree of twist in any suitable manner, either in a single stage oftwisting, or in two or more stages. Before or during twisting, or afterwinding the twisted yams into fabrics, the sizing, swelling and scouringtreatments described in the specifications previously referred to may beemployed to assist in improvingthe crepe effect on the fabrics. It

is preferable to employ yarns of fine filament denier, and preferably totwist the yarns to a high or very high degree.

It is possible to produce a differential shrinkage "which is ofadvantage in the twisted yarns either by applying the shrinking agentintermittently along the length of the yarns, or by using yarns shrunkand others not, or between whose component filaments different degreesof shrinking have been effected. Likewise the yarns may consist 'of twoor more different types of cellulose derivative yarn, for example wetand dry spun yarns or yarns of different esters or ethers ,or ofdifferent ester or ether content, and such different filaments may meshrunk with shrinking agents in concentration before incorporation inthe yarns for twisting, or after such concentration.

Highly twisted crpe threads consisting of shrunk yarns as describedabove may be incorporated in the fabrics in any suitable r'nanner.' Forexample, the weft alone may be wholly or partially .composed of suchthreads or the warp may also contain them. It is found particularlyconvenient however, in general, to employ threads of relatively lowtwist in the warp and to employ in the weft both crepe threads having aleft-hand twist and crepe threads having a right-hand twist. Suchthreads may be disposed in the fabrics in any convenient manner, forexample pairs of threads of left-hand twist may alternate with pairs ofthreads of right-hand twist. A further method of constructing thefabrics is to weave composite crepe threads consisting of a yarn of hightwist doubled with a yarn of low twist, or consisting of two yarns ofhigh but opposite di rection of twist, the yarns being prepared and thefabrics subsequently treated in accordance with the processes of theinvention. In-this manner crepe fabrics maybe readily produced withoutthe necessity for the employment of a loom capable of weaving twodifferent types of yarn such as is necessary when alternate picks ofyarn of lefthanded twist and yarn of right-handed twist are to be woven.In this connection reference is made t Br. Patents NOS. 332,903 and375,355.

shrunk by a treatment with methylenechloride or the like as describedabove.

By way of illustration the following example is given of the applicationof the invention to yarns of cellulose acetate. A cellulose acetate yarnof 100 denier and 42 filaments is treated with a shrinking mixture of 3parts by volume of methylene chloride, to 1 part of benzene, whereby thedenier of the yarn is increased to 112 denier. The yarn is then twistedto 20 turns per inch, and steamed for 5 minutes, after which a furtherstage of twisting is applied, bringing the total twist to 65 turns perinch. The crepe yarn obtained has a high strength, and a high breakingextension. The yarn is woven, '72 picks per inch into a plain warp ofcellulose acetate yarns, of 75 denier having 120 ends per inch, twopicks of left-hand twist alternating with two picks of right-hand twist.The resulting fabric is strong, has a good crepe figure, and a pleasanthandle.

' While the invention has been described above more. particularly withreference to yarns composed of or containing acetone-soluble celluloseacetate, it may be applied to yarns made from or containing othercellulose acetates or other esters, for example, cellulose formate,propionate, butyrate, nitroacetate and the like, or made from orcontaining cellulose ethers, for instance methyl,

I ethyl or benzyl cellulose, or made from or consome of whose componentfilaments have been taining cellulose ether-esters. Furthermore, in'addition to filaments of cellulose derivatives, the

such as natural silk or reconstituted cellulose. Again, the cellulosederivative filaments which the yarns contain may be wholly or partiallyin the form of staple lengths, alone or in admixture with staple fibresof other materials such as silk, wool, cotton or the like, or withcontinuous filaments of other materials such as silk, or reconstitutedcellulose artificial silk filaments.

What we claim and desire to secure by Letters Patent is: v

1. In the method of producing crepe yarns. by

shrinking yarns containing cellulose acetate with a latent solvent forthe cellulose acetate and applying a high degree of twist thereto, thesteps of applying to the yarns, during the treatment with said latentsolvent, a tension of such a nature that the shrinking of the yarns isrestricted and then decreasing thectension whereby restraint upon theshrinkage of the yarns is removed.

2. Method of producing crepe yarns, which comprises treating yarnscontaining cellulose derivatives with-a latent solvent for the cellulosederivative, whileflrst maintaining the yarns under restricted. thendecreasing the tension so as to a tension of such a nature thatshrinking of the yarns under the action of the latent solvent is u2,059,423 yarns may contain filaments of other materials removerestraint from the yarns and to permit shrinkage to take place, and thenapplying a high degree or twist to the shrunk yarns.

3. In the method of producing crepe yarns by shrinking yarnscontainingv' cellulose derivatives witha latent solvent for thecellulose derivative v and applying a high degree of twist thereto, the

steps of applying to the yarns, during the treatment with said latentsolvent, a tension of such a nature that the shrinking of the yarns isrestricted and then decreasing the tension whereby i restraint upon theshrinkage of the yarns is re- WILLIAM ALEXANDER DICKIE. DONALDFINLAYSON. PERCY FREDERICK COMBE SOWTER.

